Supernova Shock Breakout from a Red Supergiant

Understand

Massive stars undergo a violent death when the supply of nuclear fuel in their cores is exhausted, resulting in a catastrophic "core-collapse" supernova.

• Such events are usually only detected at least a few days after the star has exploded.
• Observations of the supernova SNLS-04D2dc with the Galaxy Evolution Explorer space telescope reveal a radiative precursor from the supernova shock before the shock reached the surface of the star and show the initial expansion of the star at the beginning of the explosion.
• Theoretical models of the ultraviolet light curve confirm that the progenitor was a red supergiant, as expected for this type of supernova.